Heart Rate is defined as the number of what per minute?

• A. Beats per minute
• B. Heart rate
• C. Cardiac output
• D. Stroke volume

Answer: (B)

This question focuses on what heart rate measures. Heart rate is the rate at which the heart beats, defined as the number of heartbeats per minute. So the correct completion is beats per minute—the unit that counts discrete heartbeats over a one-minute interval. The term heart rate itself is the label for this measure, not what is counted per minute. Cardiac output and stroke volume describe different things: cardiac output is the total volume of blood pumped per minute, while stroke volume is the amount ejected with each beat.